This chapter evaluates various criticisms of
TDM. These include claims that reduced vehicle travel harms consumers, that it
is regressive and unfair to lower-income motorists, that it is an unjustified
intervention into free markets, that TDM is harmful to economic development,
that it is ineffective, and that transit improvements are excessively expensive
and unjustified. Although some criticisms many be true in certain
circumstances, they do not apply to appropriately planned TDM programs and
strategies.

People Need to Drive

Critics often cite an example of a high
value trip (freight and business travel, commuting to school and work, visiting
family and friends) as evidence that reducing automobile travel is harmful to
consumers. But the existence of some high-value vehicle trips does not disprove
the existence of many low-value vehicle trips that can be reduced. Given better
travel options and efficient incentives, many people will significantly reduce
their automobile travel. For example, some people would like to walk, bicycle,
use transit or telework rather than drive for some trips if they were more
convenient or affordable. Similarly, a consumer might drive across town to a
distant store or restaurant if roads are free and uncongested and parking is
free, but if not will shop or eat closer to home (see Transportation
Elasticities for information on the price sensitivity of vehicle travel).

TDM is not intended to eliminate all
automobile use or an arbitrary set of vehicle trips: an efficient TDM program
reduces low value automobile trips (that is, automobile trips that consumers
consider of relatively low value either because the trips themselves are not
very important or because they can be shifted to another time, mode or
destination with little net loss), and so are most willing to forego in
response to incentives. High value vehicle trips continue, and are often
facilitated due to reduced traffic and parking congestion.

People Want to Drive

Critics often claim that “Americans (or
Canadians, British, Germans, etc.) love the mobility provided by driving,” or,
“Americans prefer big homes and wide opens spaces available in suburbs.” But
there are all sorts of Americans with a wide range of travel and housing
preferences. At the margin (that is, relative to current transport and land use
patterns), many would prefer to drive less, use alternatives more, and living
and live in more Accessible communities. For every
indicator that Americans are hopelessly in love with driving and suburbs, there
is another indicator that Americans want better alternatives. For example,
homes in New Urbanist communities tend to command a
higher value, communities with good transit service are experiencing increased
transit ridership, and many Resort Communities are
attractive due in part to their walkability.

Much of the evidence that Americans prefer
automobile travel and sprawl development ignores the tradeoffs involved. Sure,
many consumers would like to drive more and live in larger homes, if somebody
else pays, but their preference for such improvements disappears, and their
willingness to use other modes increases if they are required to pay the
incremental costs.

Put another way, reduced automobile travel
and shifts to other modes can provide savings to governments and businesses.
For example, shifting a peak-period trip from automobile to public transit,
ridesharing or nonmotorized modes can often save several dollars in avoided
roadway and parking costs. When commuters are offered these savings, many
prefer to drive less and use alternative modes more (Commuter
Financial Incentives). It is therefore wrong to suggest that all Americans
want to drive more and live in suburbs: many would prefer to drive less
and live in more urban neighborhoods, provided that they have good
options to choose from, and efficient pricing that reflects the incremental
costs and savings involved in their decisions.

TDM Harms Consumers

Some critics claim that Transportation
Demand Management is harmful to consumers and an unfair punishment to motorists
(Orski, 2000; Mills, 1999; Green, 1995 Spindler, 1997; Dunn, 1998). They argue
that automobiles are a superior form of transportation so any effort to reduce
driving reduces consumer welfare. This argument ignores the fact that many TDM
strategies use positive incentives, and the possibility that consumers may
sometimes prefer to drive less and use transportation alternatives more.

The majority of TDM strategies rely on positive
incentives, as illustrated in Table 1. These positive incentives improve the
transportation and land use options available to consumers or provide financial
rewards to reduce vehicle use. With such incentives, consumers who continue
driving are no worse off, and those who reduce mileage must consider themselves
directly better off or they would not change their transport patterns.

Most TDM strategies use positive incentives:
they improve transportation options or provide new rewards for reduced driving.
Motorists who continue their current travel patterns are no worse off, and
those who reduce their mileage must be directly better off or they will not
change their travel patterns. These are in addition to indirect benefits to
motorists, such as reduced traffic congestion, facility costs and pollution emissions,
and benefits to non-motorists from reduced crash risk.

These direct consumer benefits are in
addition to indirect benefits such as reduced congestion, facility cost
savings, reduced pollution emissions, and increased traffic safety. As a result,
motorists who do not change their travel patterns can also benefit from TDM
programs.

Motorists can benefit from improved Transportation Options, even if they don’t currently use
them. Improved transport options reduces traffic and parking congestion,
pollution and crash risk, and the amount of chauffeuring motorists must perform
for family and friends (Transit Evaluation). Many
motorists value having options that can be used in an emergency (a vehicle
failure, financial or medical problems that limit driving), just as passengers
on a ship value having lifeboats that they may never actually use. This is
called “option value”, and results in a more flexible and Resilient
transportation system.

Put another way, during a typical lifecycle
there are times when alternative travel options tend to be particularly
important, including teenage and young adult years, during periods of economic
or physical constraints, and late in life when a smaller home is preferable and
driving becomes more difficult. These periods are increasing due to later
marriage and child rearing, and longer lifespans.

Motorists also benefit from TDM when it is
the most cost effective solution to transportation problems (Least-Cost
Planning). TDM can reduce congestion, road and parking facility costs,
crash risk and pollution emissions, all problems facing motorists. As a result,
it is perfectly rational for people to support improved travel choices and TDM
incentives even if they rely on automobile transportation themselves.

Most strategies that involve negative
incentives are economic transfers (Fuel Tax Increases, Parking Pricing and Road Pricing
are costs to motorists but provide revenues elsewhere in the economy) and so
their overall impacts depend on how revenues are used (Evaluating
Pricing). If revenues are returned to consumers as rebates or reduced
taxes, motorists as a group are no worse off, and those who reduce their
vehicle use are directly better off. The only real negative is the incremental
transaction costs associated with direct user charges, and these are declining
with more sophisticated Pricing Methods. Unpriced roads
and parking facilities are not really free, consumers pay for them indirectly
through taxes, higher prices for retail goods and as a substitute for other
employee benefits. Thus, the choice is not really between the benefits of free
facilities and the costs of priced facilities, but rather, between direct
and indirect facility costs. Charging users directly for roads and
parking facilities gives consumers a new opportunity to save money. If you
drive less, you save money, an option that is not available if consumers pay
indirectly. This is more economically efficient and equitable than funding
facilities indirectly (Market Principles).

Most TDM programs include both positive and
negative incentives. This tends to be most effective. As with any policy
change, some individuals may experience more benefits and others more costs,
but a well-planned TDM program can result in overall net benefits (more winners
than losers).

Optimality reflects the concept of “diminishing
returns,” which recognizes that the incremental benefits provided by a good
tend to diminish with increased consumption. This means that either too
little or too much consumption of a good can be harmful. For example, just
because you enjoy eating a piece of cheesecake does not mean that eating two
pieces will double your enjoyment and four pieces will quadruple it. Similarly,
just because driving provides consumer benefits does not necessarily mean
that more driving is better or that driving should be subsidized. Even people
who often enjoy driving often value having alternative travel options
available.

Although motor vehicle use provide
significant benefits, there is considerable evidence that at the margin (i.e.,
relative to current levels of vehicle use), many consumers would prefer to
drive somewhat less and rely more on alternative modes if they are given better
Transportation Choices and rewards for reduced driving.
For example, positive financial incentives, such as Parking
Cash Out, induce some commuters to change their travel habits, although
their participation is entirely voluntary. New Urbanist
developments, which offer more diverse transportation choices, have higher
property values than conventional developments.

Given suitable options, consumers will
choose to drive less and rely more on alternative modes. The portion of trips
made by automobile varies significantly from one town or city to another,
depending on land use and transportation policies, not just wealth, as
indicated in Table 2. This suggests that it is possible to reduce per capita
land use and vehicle travel by creating communities that provide the best of
both worlds: automobile transportation when it is appropriate, with good
transportation choices and incentives to use other modes when they are most
economically efficient. To the degree that TDM increases transportation and
land use choices, and encourages more economically efficient use of resources,
it increases consumer welfare.

Table
2 Mode
Split in Urban Areas (Pucher
and Lefevre, 1996, p. 16)

Car

Transit

Cycling

Walking

Other

Austria

39%

13%

9%

31%

8%

Canada

74%

14%

1%

10%

1%

Denmark

42%

14%

20%

21%

3%

France

54%

12%

4%

30%

0%

Germany

52%

11%

10%

27%

0%

Netherlands

44%

8%

27%

19%

1%

Sweden

36%

11%

10%

39%

4%

Switzerland

38%

20%

10%

29%

3%

UK

62%

14%

8%

12%

4%

USA

84%

3%

1%

9%

2%

The portion of urban trips made by car
varies significantly from one city to another due to differences in land use
and transportation policies.

TDM is Regressive and Unfair to Disadvantaged Populations

Green (1995) and Pisarski (1999) argue that
women and minorities benefit from increasing automobile use, and so TDM is
unfair to these disadvantaged groups. They assume that TDM consists only of
restrictions on consumer choice that force disadvantaged groups to forego desired
transport options. They ignore TDM strategies based on positive incentives that
directly benefit users, many of which tend to be particularly valuable to
people who are economically, physically or socially disadvantaged. Many TDM
strategies increase transportation Affordability and
improve travel options for non-drivers.

For example, a $50 monthly Parking Cash Out benefit represents a proportionally
greater increase in income for a $25,000 per year clerk than for a $100,000 per
year manager. Similarly, people with lower incomes and physical disabilities
often place a high value on improved transit, ridesharing, cycling and walking
conditions because they already use these options or would in order to save
money, if given the opportunity. People with physical disabilities can
particularly benefit from Universal Design, Pedestrian Improvements and Traffic
Calming.

Some TDM strategies involve regressive
fees. For example, Parking Pricing, Road
Pricing and Increased Fuel Taxes represent a
greater portion of income to a poor motorist than to one who is wealthy.
However, they are not necessarily more regressive than other fees or funding
mechanisms, particularly if there are good travel alternatives that allow
lower-income people to avoid them (Pricing Evaluation).
For example, funding a new suburban highway through a user toll is often less
regressive than through an increase in general taxes, since few poor people
drive on suburban highways, particularly if good transit and ridematching
services are available. In addition, TDM strategies that increase demand for
transit and ridesharing tend to benefit people who are transportation
disadvantaged by improving the quality of these travel alternatives (Kain,
1994).

TDM Is An Unjustified Intervention In Free Markets

Some critics argue that TDM is an
unjustified intervention in free markets. This assumes that the current
transportation market is optimal, and so any change must reduce market freedom.
But there are significant distortions in current transportation and land use markets
that favor automobile travel (Market Principles). Many
TDM strategies correct these market distortions directly, or represent “second
best” solutions to offset such distortions. Market Reforms,
Institutional Reforms, Regulatory
Reforms, Efficient Pricing, Parking
Management are examples of TDM strategies that are intended to correct
market distortions and help create more open and competitive markets.

TDM is Harmful to Economic Development

Critics sometime claim that, since
increased automobile travel is associated with economic growth, TDM must be
harmful to economic development. But this is not necessarily true (TDM and Economic Development). TDM strategies can increase
transportation system efficient, reduce overhead costs for businesses and
governments, and shift consumer expenditures to goods that provide more
economic development benefits. To the degree that TDM strategies reflect Market Principles, such as improved consumer choice,
competition, cost-based pricing and neutral public policies, they increased
productivity and economic competitiveness.

TDM is Ineffective

Some critics argue that TDM strategies are
ineffective and wasteful, and so resources should be shifted from demand
management to roadway capacity expansion (Orski 1999). They make statements
such as, “For more than a decade transportation planners have badgered
Americans (or Canadians, Southern Californians, Germans, etc.) to carpool (or
ride transit, bicycle, walk, telecommute, give up their cars, etc.) but
automobile traffic continues to grow.” Such statements misrepresent the issue.
It is comparable to asking a doctor who treated a case of athlete’s foot on a
broken leg why the patient still cannot run: the treatment may be worthwhile,
but by itself cannot be expected to solve the larger problem.

When Evaluating
transportation management strategies it is helpful to differentiate between
their travel impacts (the change per affected person or business) and take
up (also called penetration), which reflects how broadly the
strategy is applied. For example, Parking Cash Outtypically
reduces automobile use by 15-20% among commuters where it is applied, but it is
not widely applied, so its effects on total travel been small. Critics
sometimes complain that TDM is ineffective, citing continued transportation
problems such as congestion and pollution in cities that claim to have TDM
programs. However, this does not reflect a lack of impacts where TDM is
implemented, rather it is a lack of take up of the strategies: few motorists
actually face TDM strategies such as Parking Cash Out, Parking Pricing or Road Pricing.
The problem is not that TDM has been tried and failed, but rather, that it has
not really been tried in most regions. Although many communities have
implemented some TDM strategies, those that are administratively and
politically easy, few have implemented comprehensive TDM programs that include
the full range of cost-effective strategies. When it is appropriately
implemented, TDM programs often reduce 10-30% of vehicle trips at a particular
site, and a comprehensive regional TDM program can be even more effective (Success Stories).

Conventional transportation improvement
strategies also provide relatively modest benefits. For example, multi-billion
dollar investments to expand urban highways will often do little to reduce
regional Congestion, and does less to address other
transportation problems facing communities. Vehicle design improvements have
reduced per-mile Crash Rates, but this has been largely
offset by increased per capita mileage. Although vehicle pollution controls
have substantially reduced per-mile Vehicle Emission
rates, this is partly offset by increased vehicle mileage, and so urban regions
continue to experience significant pollution problems. When all impacts are
considered, TDM is often the most cost-effective solution to transportation
problems (Why TDM).

Critics often use a reductionist analysis,
that only considers one or two objectives, such as congestion or air pollution
reductions, when comparing TDM against other transport improvement options
(Pickrell, 2001). TDM tends to provide multiple benefits, so considering just
one or two objectives understates its full value (Comprehensive
Transportation Planning). On the other hand, conventional transportation
solutions often reduce one problem, but exacerbate others, so their net value
is much smaller than indicated by an analysis that focuses on just one or two
objectives (Evaluating TDM). For example, increasing
highway capacity and traffic speeds may reduce traffic congestion, but it tends
to degrade the pedestrian environment, and it often induces additional traffic
that can increase pollution emissions and crash costs over the long term (Rebound Effects). Similarly, fuel efficiency standards may
reduce per-mile energy consumption, but by reducing vehicle operating costs
they tend to increase total vehicle mileage, increasing traffic congestion and
crashes (Litman, 2006a).

When considered individually, the impacts
of most TDM strategies appear modest, affecting just a few percent of total
vehicle travel. However, their effects are cumulative and synergetic. A
comprehensive TDM program that includes an appropriate combination of
complementary strategies can have significant impacts and is often the most
cost effective solution to common transportation problems when all costs and
benefits are considered (Least Cost Planning).

The apparent effectiveness of a TDM program
is affected by the perspective and scale of Evaluation.
For example, a particular Commute Trip Reduction program
might reduce vehicle trips at participating worksites by 20%, representing 50%
of downtown employees, where 10% of regional employees are located. Commute
trips usually represent the majority of peak-period highway travel, but only
about a third of total automobile travel. As a result, this program could be
described as reducing 20% of trips a participating worksites, 10% of downtown
commute trips, 2% of regional peak-period highway travel, or less than 1% of
total regional travel. From a regional perspective the program may seem of
little significance, although a major investment to increase highway capacity
typically affects a similar portion of trips. As a result, it could be
considered equal in value to multi-billion dollar expenditures on new roads and
parking facilities, and it may be the most cost effective regional transport
investment available.

Many communities have implemented
individual TDM strategies that are worthwhile investments, such as Commute Trip Reduction programs, Rideshare
Promotion, Transit Improvements, Walking
and Cycling Encouragement, but virtually no community has implemented the
full range of TDM strategies that are technically feasible and economically
justified. Even jurisdictions committed to TDM, such as the Netherlands, New York City and Portland, Oregon, have implemented just a modest portion of the total
range of cost effective TDM strategies. The results are what would be expected:
lower rates of per capita automobile travel than what would otherwise occur
(particularly among particular groups or along particular corridors), but
significant vehicle traffic problems continue. These areas still have major Market Distortions that result in excessive automobile
use, such as Unpriced Roads (although a few major
bridges and highways are tolled, their price structure is designed to maximize
revenue rather than manage demand, and the vast majority of roadways are
unpriced), Subsidized Parking (although free parking
may be less abundant in such areas, a significant portion is still unpriced or
underpriced) and fixed Vehicle Insurance and Registration
Fees.

Critics might argue that such solutions are
politically unacceptable, but this creates a self-fulfilling prophecy: if
experts dismiss these strategies early in the planning process because they are
considered politically unacceptable, they can never be considered by the
general public. Only by considering such strategies in a Comprehensive
Transportation Planning process can their full potential benefits be
considered. Twenty years ago, few people would have predicted the development
of recycling programs, or the restrictions that now exist on smoking in public
buildings. Similarly, TDM solutions, including pricing strategies and land use
management, may become far more common in the future.

Individual TDM strategies have proven
effective and cost effective (Success Stories), and
comprehensive TDM programs that include a variety of individual strategies can
make a major contribution to solving regional or national transportation
problems. The question is not, “Can TDM solve transportation problems,” but
“How much will we allow TDM to solve transportation problems.” TDM is limited
by its institutional and political acceptance, not by its technical feasibility
or cost effectiveness.

Regulation
vs. Pricing

The following is an email exchange between Dr.
Mark Delucchi and Todd Litman comparing regulatory and pricing or TDM
solutions to transportation problems that occurred during a “New Paradigms
Dialogue” sponsored by the Transportation Research Board’s Transit
Cooperative Research Program during February 2002.

On 2/16/02, Mark
Delucchi wrote:

I would like to
provide some final guidance on thinking about the effectiveness of regulation
vs. pricing. We do know more theoretically, and by some modeling results,
then has been acknowledged here.

First, let's be
clear what we are asking about. We are asking (for example) whether the
emissions regulations that have been adopted in this country have resulted in
significantly more emissions reductions than we would have achieved had we in
1970 priced emissions at estimated marginal damage costs instead. Or, whether
adding taxes to imported oil to reflect estimated externalities of oil use
will result in more or less energy savings than large but arguably cost
effective increases in CAFE. Or, finally, whether safety standards and drunk
driving laws have saved more lives than would have pricing to incorporate
accident externalities (which, incidentally, are quite difficult to estimate).

Price changes
can affect emissions, oil-use, or accidents in three ways. First, an increase
in the price of anything correlated with driving distance will tend to reduce
driving. This may be called the VMT-reduction effect. Second, putting a price
on emissions, oil use, or accident externalities will tend to make consumers
choose cleaner, more efficient, and safer vehicles from among the existing
mix of vehicles. Finally, in theory manufacturers will recognize that
consumers ought to be willing to pay more for emission control, efficiency,
or safety features than before, and hence will devote more resources to
making all vehicles cleaner, more efficient, and safer.

Now, we have on
the one hand a reasonably good sense of the benefits of regulation. We also
have some data and modeling to indicate how the cost of driving affects
demand for driving, and some information on how the cost of fuel affects the
choice of vehicles. What I haven't seen analyzed for transportation is the
third effect: the response of manufacturers to changes in fuel prices,
emission prices, or accident prices.

We know that
emissions regulation has reduced national emissions by more than 90% for most
pollutants, and we know that CAFE standards can (cost effectively, some
argue) cut oil use in transport in half. We also know that the VMT-reduction
effect of emissions pricing or oil pricing will be on the order of 10-20% at
most, nationally. Put another way, no one can seriously argue that correct
emissions or oil taxes will reduce VMT by 90% or even 50%!! Turning now to
the vehicle choice effect, we know that differences in uncontrolled emissions
among vehicles is small compared to the difference between uncontrolled and
controlled vehicles, so that there is no way that shifting to cleaner
uncontrolled vehicles could reduce emissions much. And regarding energy use,
discrete choice modeling done by the California Energy Commission indicate
that the VMT-reduction and vehicle choice effects of a gasoline tax result in
several fold less energy use than does increased CAFE.

Thus far we have
shown that regulation has much more effect on emissions and energy use than
does the VMT-reduction and vehicle-choice effects of pricing. That is, the
implementation of emission-control technology or fuel-efficiency technology
does far more to reduce emissions or oil use than does VMT reduction or
switching models. So, the question becomes simply this: which is the most
effective way to get emission-control technology or fuel-efficiency
technology: by direct regulation, or by indirect demand-side pricing? The
answer to me is obvious, although I can't say that I have seen any empirical
work on this.

I believe the
same can be said about safety regulation vs. accident externality pricing.

Hope this helps!

Sincerely,

Mark Delucchi

Research
Scientist

Institute of Transportation Studies

University of California

On 2/20/02, Todd
Litman wrote:

I agree with Dr.
Delucchi that if each transportation problem is considered individually
(i.e., from a “reductionist” perspective), it usually appears that regulation
is more cost effective than pricing. However, when a more comprehensive
approach is used that considers the full range of impacts together, the value
of pricing increases and the value of simple regulation declines. My
conclusion is that a combination of regulation and pricing is usually best.

For example, as
Dr. Delucchi describes, emission pricing by itself only justifies a modest
reduction in VMT and emissions. Modeling by the late Greig Harvey predicts
that a fee based on measured tailpipe emissions, which averages about one
cent per vehicle-mile (but higher for more polluting vehicles) would reduce
mileage by about 2%, but energy consumption would decline by 7% and air
pollution emissions would decline by almost 20% (Harvey and Elizabeth, 1998).
This is smaller than the emission reductions that have been achieved in the
past through regulations, (although most technology experience diminishing
marginal returns so it is likely that that regulations may be less cost
effective for achieving additional emission reductions).

When other costs
and benefits are considered, the value of pricing tends to increase. For
example, road and parking pricing, weight-distance fees and Pay-As-You-Drive
insurance, can be justified on congestion reductions, facility cost savings
and equity objectives, and so their emission reductions are provided at zero
incremental cost. A study I was involved in indicates that these pricing
reforms if implemented to the degree that each is justified on efficiency
grounds could reduce total VMT by about a third (Litman, Komanoff and Howell,
1998).

Pricing actually
provides more comprehensive emission reduction benefits. The pollution
control regulations only reduce tailpipe emissions, and actual emission
reductions tend to be significantly lower than emission tests indicate due to
deterioration over time. Some other emissions, such as tire and brake
particulates and road dust, are related to VMT.

Most regulatory
strategies reduce just one or two problems, and they often have unintended
consequences that exacerbate other problems (Litman, 2005). On the other
hand, pricing strategies tend to help address several problems. Only when all
of these impacts are considered can we conclude which combination of
strategies are truly optimal.

For example, a
50% increase in average vehicle efficiency from CAFE standards would increase
VMT by about 10% (based on a -0.2 elasticity of VMT wrt pre-mile fuel cost).
Although this still leaves a 40% net reduction in energy consumption, it will
increase other traffic impacts, including congestion, road and parking
facility costs, crashes, urban dispersion, traffic noise and non-tailpipe air
pollution by about 10% each. Is the energy savings worth these increased
costs? Not according to most cost estimates, which put air pollution and
energy externalities among the middle-range costs, below crash costs, road
and parking facility costs, and about equal to congestion costs (Litman,
2001).

Transit is Excessively Expensive and Unjustified

Some critics argue that Transit
investments, particularly new urban rail projects, are not cost effective and
require excessive public subsidies. They point out that such projects require
large subsidies per additional rider, and are not the most cost effective way
to solve a particular problem such as traffic congestion or air pollution. But
such criticism tends to ignore several significant points (Transit
Evaluation).

Public transit is like a house: it has many
functions and offers many benefits. Just because people generally sleep in
their home does not mean that sleeping is the only function of a house,
or that homes should be judged simply on the number, size and quality of their
bedrooms. In addition to sleeping, homes provide a place to cook, eat, visit and
perform various types of work, as well as providing storage space and
investment value. In addition some people own houses that they rent for income,
cottages that they use for recreation, and guest houses that they maintain to
accommodate visitors.

Similarly, public transit provides many
different functions and benefits to society. It can help reduce traffic
congestion, road and parking facility costs, consumer costs, crash risk, energy
consumption and environmental impacts, provide mobility for non-drivers, help
create more accessible land use patterns, and provide mobility in emergencies.
Because of these multiple benefits, a greater subsidy per trip may be justified
than for an automobile trip that does not provide such benefits.

Most transit is provided under urban-peak
travel conditions, where costs of all modes tend to be high. Although the
subsidy required for an additional peak-period urban transit trip is high, the
full Cost of accommodating an additional peak-period
urban automobile is also high.

Rail transit can provide a catalyst for
more efficient land use, which can provide additional vehicle travel reductions
and environmental benefits. Relatively high per-trip subsidies may be justified
for transit investments that support long-term transportation and land use
objectives.

Although subsidies per transit
passenger-mile may appear high, transit-dependent people travel about a third
as much as motorists per year, so their per capita annual subsidy is usually
lower than that received by motorists, particularly if roads, parking and other
external costs are considered.

This is not to suggest that all transit
projects are worthwhile or optimal. However, it is important to consider these
additional factors when evaluating the benefits and cost effectiveness of
transit investments and subsidies.

Conclusion

Many arguments used by critics of TDM are
technically incorrect or only apply in some situations. Transportation Demand
Management strategies can be effective and provide significant direct and
indirect benefits to a community. Of course, when implemented inappropriately
TDM programs can be wasteful and unfair. To be effective, TDM strategies must
be thoughtfully planned and implemented. However, it is wrong to dismiss TDM in
general as being harmful to consumers, regressive or wasteful.

CFTE (2005),
Building Communities Through Public Transportation: A Guide for Successful
Transit Initiatives, Center for Transportation Excellence, for the Public
Transportation Partnership for Tomorrow (www.cfte.org/Building_Communities.pdf).

Wendell Cox (1999), The
President’s New Sprawl Initiative: A Program in Search of a Problem,
Heritage Foundation (www.heritage.org).

Douglass Lee (1992), “An Efficient Transportation and
Land Use System,” in Privatization and Deregulation in Passenger
Transportation: Selected Proceedings of the 2nd International Conference, Espoo, Finland.

Todd Litman (2011), The First
Casualty of a Non-Existent War: Evaluating Claims of Unjustified Restrictions
on Automobile Use, and a Critique of 'Washingtons War On Cars And The Suburbs',
Victoria Transport Policy Institute (www.vtpi.org);
at www.vtpi.org/carwars.pdf.

Raymond Novaco and Cheryl Collier
(1994), Commuting Stress, Ridesharing, and Gender: Analyses from the 1993
State of the Commute Study in Southern California, University of California Transportation Center (Berkeley), Working
Paper #208 (www.uctc.net).

This Encyclopedia is
produced by the Victoria Transport Policy Institute to help improve
understanding of Transportation Demand Management. It is an ongoing project.
Please send us your comments and suggestions for improvement.